Prognostic marker for cryoglobulinemic vasculitis and B cell malignancies in HCV infected patients

Abstract

The invention provides methods and compositions for early diagnosis and treatment of a disease associated with a specific antibody by employing the detection of a cross-idiotypic epitope on the specific antibody to detect the cells that produce the antibody before the development of clinical symptoms of the disease.

What is claimed is: 
     
       1. A method for detecting an over-expressed immunoglobulin nucleic acid sequence from a clonally expanded B cell population in a subject comprising (a) providing a cDNA sample from the subject, wherein the subject is infected with hepatitis C virus (HCV) but is asymptomatic for cryoglobulinemic vasculitis and B cell malignancy; (b) contacting the sample with a set of first primers and second primers wherein said set of first primers and second primers comprises a first primer and a second primer that flank the complementary determining region 3 (CDR3) sequence, a first primer and a second primer that flank a VH-D-JH sequence and a first primer and a second primer that flank a VK-JK sequence in Ig-encoding transcripts; (c) amplifying said CDR3 sequence, said VH-D-JH sequence, and said VK-JK sequence; and (d) detecting an overexpressed nucleic acid sequence encoding an amino acid sequence comprising IgH V1-69 or IgHV V 3-7, VK325 or VK 328, JH4 or JH3, Jk1, and a D region consensus sequence comprising SEQ ID NO: 1 or SEQ ID NO: 2. 
     
     
       2. The method of  claim 1 , wherein said sample is a biological fluid comprising whole blood. 
     
     
       3. The method of  claim 1 , wherein the subject is in the acute phase of HCV infection. 
     
     
       4. The method of  claim 1 , wherein the subject has not received anti-viral treatment or chemotherapy. 
     
     
       5. The method of  claim 1 , further comprising treating the subject with prednisone, cyclophosphamide, or both, following step (d).